CN105765092B - The method for processing dispersion hardening platinum composition - Google Patents

Abstract

The present invention relates to a method for processing a dispersion-hardened platinum composition, wherein there is provided a composition comprising at least 70 wt. A three-dimensional body of a dispersion-hardened platinum composition of a non-noble metal of yttrium; cold forming the three-dimensional body of the dispersion-hardened platinum composition, whereby during cold forming the transverse reducing the cross-sectional area by at most 20%; and subsequently subjecting the cold-formed three-dimensional body to a temperature treatment, wherein the cold-formed product is tempered at at least 1100° C. for at least 1 hour. Furthermore, the present invention describes a method of manufacturing products made of a dispersion-hardened platinum composition as well as a dispersion-hardened platinum material obtainable according to the above-specified processing method. Furthermore, the use of a dispersion hardened platinum material is described.

Description

Method of processing dispersion hardened platinum compositions

technical field

The present invention relates to methods of processing dispersion hardened platinum compositions. The invention also describes a method of making a product from a dispersion hardened platinum composition. The invention also relates to the products obtainable by said process and to the use of such platinum compositions.

Background technique

Shaped bodies made of platinum are often used in high-temperature processes, where the material must have high corrosion resistance. For example, platinum components exposed to mechanical loads are used in the glass industry, such as stirrers or fiberglass spray tanks (Düsenwannen). However, its low mechanical strength at high temperature is a disadvantage when platinum is used as a material. Therefore, dispersion hardened platinum compositions are commonly used in the high temperature processes mentioned above.

The manufacture and processing of such materials is known, for example, from publications GB 1 340 076 A, GB 2 082 205 A, EP 0 683 240 A2, EP 1 188844 A1 and EP 1 964 938 A1.

Fabrication of parts from a dispersion hardened platinum composition is usually first produced as an ingot, which is hot rolled. The semi-finished product obtained can then be cold formed.

Forming at low temperatures enables cost-effective adaptation to individual specifications. However, it has been found that the mechanical properties of the dispersion-hardened platinum material are not good enough, or at least could be better, especially for the forming technique. The service life of this part is too short for some applications, or has to be replaced more often than desired. This replacement is associated with high costs. However, forming at high temperatures (so-called thermoforming) is very expensive and difficult because of the complexity of the machinery used for this purpose.

Contents of the invention

Therefore, the object of the present invention is to overcome the disadvantages of the prior art. In particular, the method should allow cost-effective adaptation of components made of platinum compositions to individual targets while improving the mechanical properties. At the same time, the parts obtained should have a long service life and exhibit as little wear as possible. Furthermore, the method should be easy and cost-effective to implement. Furthermore, the formed parts should have good machinability, especially weldability.

The object of the present invention is solved by a method for processing a dispersion-hardened platinum composition, characterized in the following steps:

providing a three-dimensional solution of a dispersion-hardened platinum composition comprising at least 70 wt. body;

cold forming said dispersion hardened platinum composition, wherein the cross-sectional area of a three-dimensional body made from said dispersion hardened platinum composition is reduced by up to 20% during cold forming; and

• Subsequent temperature treatment of the cold-formed three-dimensional body, wherein the cold-formed product is tempered at at least 1100° C. for at least 1 hour.

Within the scope of the present invention, a cross section is to be understood as the region of a plane formed by a (imaginary) section through the three-dimensional body. The plane defined by the cross-section does not necessarily have to be perpendicular or substantially perpendicular to the longest dimension of the three-dimensional body.

The weight percentages given above add up to 100%, where the weight of the non-noble metal is based on the weight of the metal.

Preferably, at least 70%, preferably at least 90%, of the one or more non-noble metals are oxidized by oxygen. Here, all oxidation stages of the non-noble metal are taken into account, whereby preferably at most 30 atomic %, particularly preferably at most 10 atomic %, of the non-noble metal is present as metal, ie in formal oxidation stage 0.

Preferably, the dispersion-hardening platinum composition contains 0.05% to 0.5% by weight, particularly preferably 0.1% to 0.4% by weight, especially preferably 0.15% to 0.3% by weight, of the at least partially oxidized non-noble metal.

A high proportion of non-noble metal oxides leads to a longer service life of the three-dimensional body under mechanical load. Three-dimensional bodies with a low proportion of non-noble metal oxides exhibit advantages with regard to the processability of the three-dimensional bodies, for example weldability.

In the method of the invention a three-dimensional body is provided. The term three-dimensional body is to be understood broadly here. The three-dimensional body may preferably be in the form of a metal sheet, tube or wire, for example.

In this paper, the size of the three-dimensional body in the three dimensions of space is not subject to any particular restriction, but can be selected according to requirements. Thus, the provided metal sheets, tubes or wires can have a thickness of, for example, 0.1 mm to 10 mm, preferably 0.3 mm to 5 mm. In this context, the thickness refers to the minimum size of a three-dimensional body. In the case of a wire this is the diameter, in the case of a tube this is the difference between the outer and inner diameter, which is also known as the wall thickness of the tube.

Platinum compositions usable according to the invention comprise at least 70% by weight of platinum and up to 29.95% by weight of other noble metals. Thus, the composition may consist essentially of platinum and the at least partially oxidized non-noble metals described above. Thus, the platinum material may be pure platinum with the exception of usual impurities, mixed with at least partially oxidized non-noble metal. Furthermore, the platinum composition may also contain other noble metals, in which case the platinum composition is a platinum alloy.

According to the invention it can be provided that the further noble metal is selected from the group consisting of ruthenium, rhodium, gold, palladium and iridium.

The provided three-dimensional body is cold formed according to the method of the invention. The term "cold forming" is known in the art, wherein said forming takes place at relatively low temperatures below the recrystallization temperature of the platinum composition, and includes in particular drawing, pressing, deep drawing, cold rolling, cold forging Hit and squeeze. Shaping involves deformation of 3D volumes over a large range. Preferably it can be provided that the three-dimensional body is deformed over at least 50%, particularly preferably at least 75%, especially preferably at least 95%, of its volume. Thus, if the three-dimensional body is, for example, a metal sheet, preferably at least 50%, particularly preferably at least 75%, especially preferably at least 95%, of the surface of the metal sheet is exposed to force and/or pressure, for example by rolling. In the case of a metal sheet, this surface can be reduced to a surface perpendicular to the smallest dimension (thickness) of the three-dimensional body. If the three-dimensional body is for example a thread or a tube, preferably at least 50%, particularly preferably at least 75%, especially preferably at least 95%, of the length of the thread or tube is exposed to force, for example drawn.

It is important for the invention that relatively little forming takes place during cold forming. Preferably, the cross-sectional area of the three-dimensional bodies produced from the dispersion-hardened platinum composition is reduced by at most 20%, particularly preferably at most 18%, especially preferably at most 15%. These values are based on the most reduced volume cross-sectional area. In the case of metal sheets rolled in one direction only, a reduced cross-sectional area results, for example, from the thickness and unstretched dimensions of the three-dimensional body. In the case of wires or tubes, a reduction in the cross-sectional area results from a change in diameter and/or wall thickness. Since the volume of the three-dimensional body does not change due to molding, at least one cross-sectional area must expand during the molding process. For example, in the case of metal sheets, tubes or wires, the length increases during the forming process, whereby the area in the direction of increasing length also becomes larger. The direction of action of the forming force is in particular parallel or perpendicular to the plane defined by the cross-sectional area.

A preferred embodiment provides that the cross-sectional area of the three-dimensional body produced from the dispersion-hardened platinum composition is reduced by at least 5%, preferably by at least 8%, particularly preferably by at least 10%, during cold forming.

It has been found that the internal destruction of the dispersion hardened three-dimensional bodies does not significantly contribute to the improvement of the creep strength during forming with a reduction in cross-sectional area of less than 5% in each case and subsequent annealing. The smaller the change in cross-sectional area per forming step within the mentioned ranges, compared to forming with a reduction in cross-sectional area of 5% to 20%, preferably 8% to 18%, especially preferably 10% to 15% process, the smaller the effect on the improvement of creep strength.

Furthermore, it can be provided that the wire is drawn or pressed during cold forming, wherein the cross-sectional area of the wire produced from the dispersion-hardened platinum composition is reduced by at most 20%, particularly preferably at most 18%, during cold forming, especially preferably Up to 15%, or the sheet metal is rolled, drawn, pressed or extruded during cold forming, whereby the cross-sectional area of sheet metal made from the dispersion hardened platinum composition or the sheet metal is reduced during cold forming The thickness is reduced by at most 20%, particularly preferably at most 18%, especially preferably at most 15%, or the tube is rolled, drawn or pressed during cold forming, whereby the dispersion hardened platinum composition will be made during cold forming The cross-sectional area of the tube is reduced by at most 20%, particularly preferably at most 18%, especially preferably at most 15%.

According to the invention it can be provided that no microcracks or pores or less than 100 microcracks and/or less than 1000 pores per cubic millimeter develop within the dispersion-hardened platinum composition during cold forming.

The cold forming of the three-dimensional body is followed by a temperature treatment of the cold-formed three-dimensional body, wherein the cold-formed product is tempered at at least 1100° C. for at least 1 hour. The tempering treatment may preferably be carried out for at least 90 minutes, more preferably at least 120 minutes, particularly preferably at least 150 minutes, especially preferably at least 180 minutes. The temperature at which the tempering treatment is carried out may preferably be at least 1200°C, particularly preferably at least 1250°C, more particularly preferably at least 1300°C, especially preferably at least 1400°C.

Furthermore, it can be provided that during the temperature treatment the cold-formed three-dimensional body is tempered at a temperature of at least 1250° C. for at least 1 hour, preferably at a temperature of 1400° C. for 1 to 3 hours.

The longer the tempering process and the higher the temperature at which the temperature treatment is carried out, the better the mechanical properties of the cold-formed shaped body. However, the improvement in mechanical properties saturates at a certain point and there is a risk of strong grain growth, which in turn deteriorates the mechanical properties. Furthermore, the costs of this method increase with the duration and tempering temperature. The minimum temperature in the tempering process is 1100°C. The maximum temperature during the tempering treatment is 20° C. lower than the melting temperature of the respective dispersion hardened platinum composition.

Preferably, it can be provided that defects of the three-dimensional body are repaired by means of one or more temperature treatments of the cold-formed three-dimensional body.

The method according to the invention may also provide that the cross-sectional area of the three-dimensional body is reduced by more than 20% by successively carrying out several cold formings, wherein in each individual cold forming the dispersion hardened platinum composition The cross-sectional area of the produced three-dimensional body is reduced by at most 20%, particularly preferably at most 18%, especially preferably at most 15%, and the cold-formed three-dimensional body is subjected to a temperature treatment between each cold forming, during which the cold The molded product is tempered at at least 1100° C. for at least 1 hour.

In this context, "between each cold forming" is to be understood as meaning a temperature treatment preferably at least 1100°C for at least 1 hour after each cold forming, so that the number of cold forming steps and the number of tempering treatment steps equal.

The advantage of performing multiple cold forming and temperature treatments is that even larger formings can be achieved with relatively easy and uncomplicated cold forming and temperature treatments performed without weakening the dispersion hardened platinum composition, i.e. without reducing the e.g. creep strength. It was even surprisingly found that the improvement in creep strength increases with increasing number of forming steps and annealing steps.

A preferred embodiment of the invention provides that, in the case of several successive cold formings, each cold forming reduces the cross-sectional area of the three-dimensional body produced from the dispersion-hardened platinum composition by at least 5%, preferably by at least 8%, particularly preferably At least 10%.

Forming steps comprising less than 5% of the cross-sectional area of the dispersion hardened three-dimensional body per forming step and subsequent annealing did not contribute significantly to improving creep strength. The smaller the change in cross-sectional area per forming step within the range mentioned, the less effect the improvement of creep strength has on forming compared with a reduction in cross-sectional area of 5% to 20%. Furthermore, the multiple successive forming and annealing steps complicate the process and are therefore uneconomical. This is the more the case the greater the number of shaping steps required to reach the desired final dimensions of the dispersion hardened three-dimensional body. The preferred number of forming steps is 8 in order to achieve the desired final dimensions. The stated number of forming steps is a good compromise between economy and improvement of mechanical properties.

Preferably it can be provided that during the last temperature treatment after the last cold forming of the three-dimensional body, the cold-formed product is tempered at least 1550°C for at least 24 hours, at least 1600°C for at least 12 hours, at least 1650°C The tempering treatment at a temperature of 1690° C. to 1740° C. for at least 1 hour or at least 30 minutes at a temperature of 1690° C. to 1740° C.

The microdefects to be repaired by the dispersion hardened platinum composition in its final form are substantially eliminated with said final step and the product so produced therefore has extremely high creep strength.

Any dispersion hardened platinum composition is suitable as a starting product for this processing method. However, surprising advantages are obtained by using semi-finished products which have usually been subjected to the thermoforming process. Before cold forming, the dispersion-hardened platinum composition can be shaped using a thermoforming process at a temperature of at least 800°C, preferably at a temperature of at least 1000°C, particularly preferably at a temperature of at least 1250°C.

Another subject-matter of the invention is a method for the manufacture of a product from a dispersion-hardening platinum composition, characterized in that it consists of at least 70 wt. The composition of weight % of at least one non-noble metal selected from ruthenium, zirconium, cerium, scandium and yttrium is produced by at least partial oxidation of said one or more non-noble metals.

Preferably, at least 70%, preferably at least 90%, of said one or more non-noble metals are converted into metal oxides.

The treatment of the one or more non-noble metals may preferably be carried out at a temperature of 600°C to 1600°C in an oxidizing atmosphere, preferably at a temperature of 800°C to 1000°C in an oxidizing atmosphere.

The described method of making a product made from a dispersion hardened platinum composition may preferably be combined with the aforementioned processing methods and embodiments thereof described herein as preferred.

Another subject-matter of the invention is a dispersion-hardened platinum material obtainable by a processing method and/or by a method for producing a product from a dispersion-hardened platinum composition. The subject matter offers a combination of excellent mechanical properties with excellent processability and/or cost-effective and uncomplicated producibility.

Preferably it can be provided that the cylindrical three-dimensional body made of the dispersion-hardened platinum material withstands a tensile load of 9 MPa in the length direction of the three-dimensional body at a temperature of 1600° C. for at least 40 hours without cracking, preferably for at least 50 hours without cracking, particularly preferably resistant to at least 100 hours without cracking, and/or metal sheets made of said dispersion-hardened platinum material having a rectangular cross-section of 0.85 mm x 3.9 mm and a length of 140 mm, which in Placed in a furnace chamber at 1650°C on two parallel columns with a circular cross-section and a diameter of 2 mm at a distance of 100 mm and the metal sheet is loaded with a weight of 30 g in the middle, the sag after 40 hours is less than 40 mm, preferably less than 30 mm sag, particularly preferably less than 20 mm sag, very particularly preferably less than 14 mm sag.

According to the invention, a cylindrical three-dimensional body is to be understood as a straight cylindrical body, in particular a cylindrical body, or a cylindrical body with a non-circular or circular base. In particular, the columnar three-dimensional body is a straight hexahedron (ie, a columnar body with a rectangular base) with a side length of 0.5 mm to 5 mm.

The length of a cylindrical three-dimensional body should be understood as the longest dimension. In the case of a wire or tube, the length direction is the axis of the cylindrical three-dimensional body, while in the case of a metal sheet it is a dimension in the plane of the metal sheet.

Furthermore, a dispersion-hardened platinum material having the mechanical properties described above for cylindrical three-dimensional bodies is a subject of the present invention.

It can preferably be provided that the dispersion-hardened platinum material contains 0.05% to 0.4% by weight, particularly preferably 0.05% to 0.3% by weight, of at least one at least partially oxidized non-noble metal selected from the group consisting of zirconium, cerium, scandium and yttrium. Materials with excellent mechanical properties and very good processability can in particular be provided by this embodiment.

In a particular embodiment, the dispersion hardened platinum material may be a metal sheet, tube or wire or a product formed from wire, tube and/or metal sheet.

Another subject of the present invention is a dispersion-hardened platinum material or made of a platinum composition obtainable or obtainable with the process according to the invention and/or with the method according to the invention for the manufacture of a product made from a platinum composition composed of dispersion-hardened Use of shaped three-dimensional bodies for devices used in the glass industry or laboratories.

The invention is based on the surprising realization that only such weak structural disruptions, such as lattice dislocations, were successfully introduced into the dispersion-hardened platinum composition by small cold forming (up to 20% change in cross-sectional area) so that the damage is successfully repaired with a subsequent temperature treatment so that the stability of the formed platinum composition is significantly higher than known cold forming methods of dispersion hardened platinum compositions. If a larger/stronger forming is required, this can be achieved with an upstream hot forming process or several small cold formings in succession whereby structural damage is repaired with one temperature treatment per cold forming process. As a recognition found within the scope of the present invention, the mechanical weakening of cold-formed dispersion-hardened platinum compositions is caused by a large number of severe defects, such as microcracks, delamination of the particle/matrix interface, and porosity at grain boundaries, which can be attributed to due to excessive formability and/or excessive reduction of cross-sectional area.

In particular, internal damage that cannot be repaired or can only be repaired with great effort, such as microcracks, delamination at the particle/matrix interface and porosity at grain boundaries, is prevented by gentle small cold forming. Microcracks and porosity at the grain boundaries that occur as a result of forming are particularly detrimental, since they impair the mechanical stability of the dispersion-hardened platinum composition particularly strongly. This damage was successfully avoided using the method of the present invention. Thus, for the first time, a dispersion-hardened platinum composition with extremely high mechanical stability and excellent processability, in particular weldability, has been successfully produced, which is also claimed according to the present invention.

Detailed ways

Further examples of the present invention are described below based on examples, but do not limit the scope of the present invention.

Semi-finished precursor 1

Fabrication of semi-finished precursors of metal sheets with a thickness of 2 mm by internal oxidation with Zr and Y

According to the method specified in Example 1 in EP 1 964 938 A1, a metal alloy containing PtRh10 (an alloy made of 90 wt. Ingots. The ingot is then mechanically and thermally treated. It was therefore rolled to a sheet thickness of 2.2 mm, then recrystallized annealed, and then rolled to a sheet thickness of 2 mm. The sheet metal was then oxidized at 900°C for 18 days, followed by ductile annealing at 1400°C for 6 hours.

semi-finished precursor 2

Fabrication of semi-finished precursors of metal sheets with a thickness of 3 mm by internal oxidation with Zr and Y

According to the method specified in Example 1 in EP 1 964 938 A1, a metal alloy containing PtRh10 (an alloy made of 90 wt. Ingots. The ingot is then mechanically and thermally treated. It was therefore rolled to a sheet thickness of 3.3 mm, then recrystallized annealed, and then rolled to a sheet thickness of 3 mm. The sheet metal was then oxidized at 900°C for 27 days, followed by ductile annealing at 1400°C for 6 hours.

Semi-finished precursor 3

Fabrication of semi-finished precursors of metal sheets with a thickness of 3 mm by internal oxidation with Zr, Y and Sc

Casting containing PtRh10 (an alloy made of 90 wt% Pt and 10 wt% Rh) and 2120 ppm non-noble metals (1800 ppm Zr, 270 mm Y and 50 ppm Sc). The ingot is then mechanically and thermally treated. It was therefore rolled to a sheet thickness of 3.3 mm, then recrystallized annealed, and then rolled to a sheet thickness of 3 mm. The sheet metal was then oxidized at 900°C for 24 days, followed by ductile annealing at 1400°C for 6 hours.

Example 1

According to the invention, the semi-finished precursor 1 obtained according to the aforementioned method with a thickness of about 2 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 1.7 mm and subsequently annealed at 1400°C for 4 hours. The metal sheet was then rolled to 1.4 mm and annealed at 1400°C for 2 hours. The metal sheet was then further rolled to 1.2 mm and annealed at 1400° C. for 2 hours. The sheet metal was then rolled to 1 mm and annealed again at 1400°C. This was followed by rolling to a final thickness of 0.85 mm and a final anneal at 1100° C. for 4 hours. The cross-sectional area of each rolling step is reduced by 20%.

Example 2

Example 1 was essentially repeated, but with final annealing at 1700° C. for 1 hour after rolling to a final thickness of 0.85 mm.

Example 3

According to the invention, the semi-finished precursor 2 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 2.4 mm and subsequently annealed at 1150°C for 4 hours. The metal sheet was then rolled to 1.92 mm and annealed at 1150°C for 4 hours. The metal sheet was then rolled to 1.53 mm and annealed at 1150°C for 4 hours. This rolling and annealing step was also repeated three times, whereby the metal sheet was rolled first to 1.22 mm, then to 0.99 mm, then to 0.8 mm and annealed at 1150° C. for 4 days after each rolling step Hour. The cross-sectional area of each rolling step is reduced by 20%.

Example 4

According to the invention, the semi-finished precursor 2 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 2.4 mm and then annealed at 1300°C for 4 hours. The metal sheet was then rolled to 1.92 mm and annealed at 1300°C for 4 hours. The sheet metal was then rolled to 1.53 mm and annealed at 1300°C for 4 hours. This rolling and annealing step was also repeated three times, whereby the metal sheet was rolled first to 1.22 mm, then to 0.99 mm, then to 0.8 mm and annealed at 1300° C. for 4 days after each rolling step Hour. The cross-sectional area of each rolling step is reduced by 20%.

Example 5

According to the invention, the semi-finished precursor 2 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 2.4 mm and subsequently annealed at 1400°C for 4 hours. The metal sheet was then rolled to 1.92 mm and annealed at 1400°C for 4 hours. The metal sheet was then rolled to 1.53 mm and annealed at 1400°C for 4 hours. This rolling and annealing step was also repeated three times, whereby the metal sheet was rolled first to 1.22 mm, then to 0.99 mm, then to 0.8 mm and annealed at 1400° C. for 4 days after each rolling step Hour. The cross-sectional area of each rolling step is reduced by 20%.

Example 6

According to the invention, the semi-finished precursor 2 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 2.55 mm and then annealed at 1400°C for 4 hours. The metal sheet was then rolled to 2.16 mm and annealed at 1400°C for 4 hours. The metal sheet was then rolled to 1.84 mm and annealed at 1400°C for 4 hours. The rolling and annealing steps were repeated 5 more times, whereby the metal sheet was rolled first to 1.56 mm, then to 1.33 mm, then to 1.13 mm, then to 0.96 mm, then to 0.8 mm and annealed at 1400°C for 4 hours after each rolling step. The cross-sectional area of each rolling step is reduced by 15%.

Example 7

According to the invention, the semi-finished precursor 3 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 2.4 mm and subsequently annealed at 1150°C for 4 hours. The metal sheet was then rolled to 1.92 mm and annealed at 1150°C for 4 hours. The metal sheet was then rolled to 1.53 mm and annealed at 1150°C for 4 hours. This rolling and annealing step was also repeated three times, whereby the metal sheet was rolled first to 1.22 mm, then to 0.99 mm, then to 0.8 mm and annealed at 1150° C. for 4 days after each rolling step Hour. The cross-sectional area of each rolling step is reduced by 20%.

Example 8

According to the invention, the semi-finished precursor 3 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 2.55 mm and then annealed at 1400°C for 4 hours. The metal sheet was then rolled to 2.16 mm and annealed at 1400°C for 4 hours. The metal sheet was then rolled to 1.84 mm and annealed at 1400°C for 4 hours. The rolling and annealing steps were repeated 5 more times, whereby the metal sheet was rolled first to 1.56 mm, then to 1.33 mm, then to 1.13 mm, then to 0.96 mm, then to 0.8 mm and annealed at 1400°C for 4 hours after each rolling step. The cross-sectional area of each rolling step is reduced by 15%.

Example 9

According to the invention, the semi-finished precursor 3 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The metal sheet was rolled to 2.7 mm and subsequently annealed at 1400°C for 4 hours. The metal sheet was then rolled to 2.43 mm and annealed at 1400°C for 4 hours. The metal sheet was then rolled to 2.19 mm and annealed at 1400°C for 4 hours. The rolling and annealing steps are repeated 9 times whereby the metal sheet is rolled first to 1.97 mm, then to 1.77 mm, then to 1.60 mm, then to 1.44 mm, then to 1.29 mm mm, then rolled to 1.16 mm, then rolled to 1.05 mm, then rolled to 0.94 mm, then rolled to 0.85 mm and annealed at 1400°C for 4 hours after each rolling step. The cross-sectional area is reduced by 10% for each rolling step.

Example 10

Example 9 was essentially repeated, but with final annealing at 1700° C. for 1 hour after rolling to a final thickness of 0.85 mm.

Example 11

According to the invention, the semi-finished precursor 3 obtained according to the aforementioned method with a thickness of about 3 mm is further processed according to the following rolling and annealing steps.

The sheet metal was rolled (thermoformed) to 1.5 mm at 1100°C and subsequently annealed at 1400°C for 4 hours. The sheet metal was then rolled to 1.2 mm (first cold forming) and subsequently annealed at 1250°C for 4 hours. The metal sheet was then rolled to 1.02 mm (second cold forming) and then annealed at 1250°C for 4 hours. The rolling and annealing steps were also repeated three times, whereby the metal sheet was rolled first to 0.94 mm (third cold forming), then to 0.86 mm (fourth cold forming), then to 0.8 mm (fifth cold forming) and annealing the sheet at 1250°C for 4 hours after each rolling step. The reduction in cross-sectional area was 50% during the hot forming step, first 20%, then 15%, then 8% each during the cold forming step.

Reference example 1

The semi-finished precursor 1 obtained according to the preceding method with a thickness of about 2 mm was further processed according to conventional methods. For this, metal sheets were directly rolled to 1 mm and annealed at 1000 °C. Subsequently, the sheet metal was rolled to 0.85 mm and subjected to final annealing at 1000° C. for 1 hour.

Reference example 2

The semi-finished precursor 2 obtained according to the aforementioned method with a thickness of about 3 mm was further processed according to conventional methods. For this, metal sheets were rolled to 1.5 mm and annealed at 1400 °C for 4 hours. The sheet metal was then rolled to 0.8 mm. The cross-sectional area of each rolling step is reduced by 50%.

Reference example 3

The semi-finished precursor 3 with a thickness of about 3 mm obtained according to the aforementioned method was further processed according to conventional methods. For this, metal sheets were rolled to 1.5 mm and annealed at 1400 °C for 4 hours. The sheet metal was then rolled to 0.8 mm. The cross-sectional area of each rolling step is reduced by 50%.

Mechanical properties of the platinum material thus obtained

Creep strength according to rupture test:

To measure the creep strength, a weight corresponding to the desired load (in MPa) for the mentioned cross-section is suspended on a metal sheet sample with a cross-section of 0.85 mm x 3.9 mm and 120 mm length (Examples 1, 2, 9, 10 and Ref. 1) or 0.8 mm x 3.9 mm cross-section and 120 mm in length (Examples 3, 4, 5, 6, 7, 8, 11 and Ref. 2 and 3 ). The sample is heated by means of an electric current and kept constant at the desired temperature by means of pyrometer measurements. The time to rupture of this sample is determined and is equivalent to the creep strength.

Table 1: Creep strength at failure at 1600°C and 9 MPa load

Reference example 1 20 hours Reference example 2 35 hours Reference example 3 30 hours Example 1 50 hours Example 2 >120 hours Example 3 >100 hours Example 4 >100 hours Example 5 >100 hours Example 6 >100 hours Example 7 >100 hours Example 8 >100 hours Example 9 >100 hours Example 10 >120 hours Example 11 >100 hours

Creep strength values according to sag test

The sag test is another method for evaluating creep strength. For this purpose, will have 0.85 mm x 10 mm cross section and 140 mm length (example 1, 2, 9, 10 and reference example 1) or 0.8 mm x 10 mm cross section and 140 mm length (example 3, 4, 5, 6, 7, 8, 11 and reference examples 2 and 3) were placed on two parallel ceramic rods 100 mm apart and the middle of the sheet was loaded with a weight of 30 g. The sample was then placed in a chamber oven heated to 1650°C and the sag of the sample was measured after 40 hours.

Table 2: Creep strength according to sag test

Reference example 1 Sag > 40 mm Reference example 2 Sag 35mm Reference example 3 Sag 37mm Example 1 Sag 18 mm Example 2 Sag < 12 mm Example 3 Sag 18mm Example 4 Sag 17 mm Example 5 Sag 18mm Example 6 Sag 16 mm Example 7 Sag 17mm Example 8 Sag 17 mm Example 9 Sag 16 mm Example 10 Sag 10mm Example 11 Sag 16 mm

The above-mentioned examples demonstrate that a surprising improvement in the mechanical properties can be achieved by the measures according to the invention, whereby this improvement can be further increased by a tempering treatment step at temperatures above 1100° C., in particular above 1500° C.

The features of the invention disclosed in the above description, the claims and the examples can be essential for realizing the invention in its different embodiments individually or in any combination.

Claims (18)

1. the method for processing dispersion hardening platinum composition, it is characterised in that the following steps：Offer is comprising at least 70 weight % platinum and most At least one partial oxidation of the other noble metals of more 29.95 weight % and 0.05 weight % to 0.5 weight % selected from zirconium, cerium, scandium With the said three-dimensional body of the non-noble metal dispersion hardening platinum composition of yttrium；Dispersion hardening platinum composition described in cold forming, wherein cold The cross-sectional area of the said three-dimensional body made of the dispersion hardening platinum composition is set to reduce most 20% in forming process；And it is then right The said three-dimensional body of the cold forming carries out Temperature Treatment, wherein temperature adjustment is handled at least at least 1100 DEG C by the Cold formed products 1 hour.

2. the method according to claim 1, which is characterized in that before cold forming, the dispersion hardening platinum composition is by extremely Thermoforming process molding at a temperature of 800 DEG C few.

3. according to the method for claims 1 or 2, it is characterised in that carry out multiple cold forming in succession and make described three by cold forming Tieing up the cross-sectional area of body reduces more than 20%, wherein making by the dispersion hardening platinum composition system in each individually cold forming At the cross-sectional area of said three-dimensional body reduce most 20%, and between each cold forming to the said three-dimensional body of cold forming into trip temperature Processing, by Cold formed products, temperature adjustment is handled at least 1 hour at least 1100 DEG C in the process.

4. according to the method for claims 1 or 2, it is characterised in that the last time temperature after the last time cold forming of said three-dimensional body When degree processing, Cold formed products temperature adjustment at least 1550 DEG C is handled at least 24 hours.

5. according to the method for claims 1 or 2, it is characterised in that the last time temperature after the last time cold forming of said three-dimensional body When degree processing, Cold formed products temperature adjustment at least 1600 DEG C is handled at least 12 hours.

6. according to the method for claims 1 or 2, it is characterised in that the last time temperature after the last time cold forming of said three-dimensional body When degree processing, Cold formed products temperature adjustment at least 1650 DEG C is handled at least 1 hour.

7. according to the method for claims 1 or 2, it is characterised in that the last time temperature after the last time cold forming of said three-dimensional body When degree processing, temperature adjustment processing at least 30 minutes at a temperature of 1690 DEG C to 1740 DEG C.

8. according to the method for claims 1 or 2, it is characterised in that in cold forming process draw or suppress line, thus it is cold at The cross-sectional area of the line made of the dispersion hardening platinum composition is reduced most 20% during type, or in cold forming process Middle rolling, drawing, compacting squeeze sheet metal, thus will be made of the dispersion hardening platinum composition in cold forming process The thickness of the cross-sectional area of sheet metal or the sheet metal made of the dispersion hardening platinum composition reduces most 20%, or cold Rolling, drawing or compacting pipe in forming process, thus will be made of the dispersion hardening platinum composition in cold forming process The cross-sectional area of pipe reduces most 20%.

9. according to the method for claims 1 or 2, it is characterised in that the cold forming carries out under 500 DEG C or lower temperature.

10. according to the method for claims 1 or 2, it is characterised in that utilize the one or many of the said three-dimensional body to the cold forming Temperature Treatment repairs the defect of the said three-dimensional body.

11. according to the method for claims 1 or 2, it is characterised in that the said three-dimensional body of the cold forming is in the temperature processes In at a temperature of at least 1250 DEG C temperature adjustment handle at least 1 hour.

12. according to the method for claims 1 or 2, it is characterised in that before providing the dispersion hardening platinum composition, by extremely Few 70 weight % platinum and at least one of the other noble metals of most 29.95 weight % and 0.05 weight % to 0.5 weight % be selected from zirconium, The non-noble metal composition of cerium, scandium and yttrium is made by least partly aoxidizing one or more base metals.

13. method according to claim 12, it is characterised in that it is one or more it is non-noble metal processing in oxidizing atmosphere It is carried out at a temperature of 600 DEG C to 1600 DEG C.

14. dispersion hardening alloy platinum material, it is characterised in that the dispersion hardening alloy platinum material can be by according to claim 1 to 11 times One method or by according to the method for claim 12 or 13 obtain.

15. dispersion hardening alloy platinum material according to claim 14, it is characterised in that the column made of the dispersion hardening alloy platinum material The tolerance of shape said three-dimensional body at a temperature of 1600 DEG C on the length direction of said three-dimensional body the drawing load of 9 MPa at least 40 hours without opening It splits, and/or it is characterized in that the rectangular cross section with 0.85 mm x, 3.9 mm made of the dispersion hardening alloy platinum material With the sheet metal of the length of 140 mm, having for two parallel arrangements at a distance of 100 millimeters is placed in 1650 DEG C of furnace chamber On the mast of circular cross section and 2 mm dias and make the sheet metal in the weight of 30 g of middle part load, after 40 hours It is sagging to be less than 40 millimeters.

16. dispersion hardening alloy platinum material according to claim 14, it is characterised in that the dispersion hardening alloy platinum material is sheet metal, pipe Or line or the product that is formed by line, pipe and/or sheet metal.

17. dispersion hardening alloy platinum material according to claim 14, it is characterised in that the dispersion hardening alloy platinum material includes 0.05 weight At least one base metal selected from zirconium, cerium, scandium and yttrium at least partly aoxidized of amount % to 0.3 weight %.

18. dispersion hardening alloy platinum material according to claim 14 is processed more according to the method for any one of claim 1 to 11 Dissipate hardening alloy platinum material or according to dispersion hardening alloy platinum material made of claim 12 or 13 for making in glass industry or laboratory The purposes of device.